RESUMEN
The main manifestations of Takotsubo syndrome (TTS) are a spherical expansion of the left ventricle or near the apex and decreased systolic function. TTS is mostly thought to be induced by emotional stress, and the induction of TTS by severe infection is not often reported. A 72-year-old female patient with liver abscess reported herein was admitted due to repeated fever with a history of hypertension and impaired glucose tolerance. Her severe infection caused TTS, and her blood pressure dropped to 80/40 mmHg. IABP treatment was performed immediately and continued for 10 days, and comprehensive medication was administered. Based on her disease course and her smooth recovery, general insights and learnings may be: Adding to mental and other pathological stress reaction, serious infections from pathogenic microorganism could be of great important causation of stress reaction leading to TTS, while basic diseases such as coronary heart disease, hypertension, and diabetes were be of promoting factors; In addition to effective drug therapies for TTS, the importance of the timely using of IABP should be emphasized.
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Hipertensión , Absceso Hepático , Cardiomiopatía de Takotsubo , Humanos , Femenino , Anciano , Cardiomiopatía de Takotsubo/complicaciones , Cardiomiopatía de Takotsubo/diagnóstico por imagen , Cardiomiopatía de Takotsubo/tratamiento farmacológico , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Absceso Hepático/complicacionesRESUMEN
OBJECTIVES: To investigate the long-term outcome of patients with acute ST-segment elevation myocardial infarction (STEMI) and a chronic total occlusion (CTO) in a non-infarct-related artery (IRA) and the risk factors for mortality. METHODS: The enrolled cohort comprised 323 patients with STEMI and multivessel diseases (MVD) that received a primary percutaneous coronary intervention between January 2008 and November 2013. The patients were divided into two groups: the CTO group (n = 97) and the non-CTO group (n = 236). The long-term major adverse cardiovascular and cerebrovascular events (MACCE) experienced by each group were compared. RESULTS: The rates of all-cause mortality and MACCE were significantly higher in the CTO group than they were in the non-CTO group. Cox regression analysis showed that an age ≥ 65 years (OR = 3.94, 95% CI: 1.47-10.56, P = 0.01), a CTO in a non-IRA(OR = 5.09, 95% CI: 1.79 ~ 14.54, P < 0.01), an in-hospital Killip class ≥ 3 (OR = 4.32, 95% CI: 1.71 ~ 10.95, P < 0.01), and the presence of renal insufficiency (OR = 5.32, 95% CI: 1.49 ~ 19.01, P = 0.01), stress ulcer with gastraintestinal bleeding (SUB) (OR = 6.36, 95% CI: (1.45 ~ 28.01, P = 0.01) were significantly related the 10-year mortality of patients with STEMI and MVD; an in-hospital Killip class ≥ 3 (OR = 2.97,95% CI:1.46 ~ 6.03, P < 0.01) and the presence of renal insufficiency (OR = 5.61, 95% CI: 1.19 ~ 26.39, P = 0.03) were significantly related to the 10-year mortality of patients with STEMI and a CTO. CONCLUSIONS: The presence of a CTO in a non-IRA, an age ≥ 65 years, an in-hospital Killip class ≥ 3, and the presence of renal insufficiency, and SUB were independent risk predictors for the long-term mortality of patients with STEMI and MVD; an in-hospital Killip class ≥ 3 and renal insufficiency were independent risk predictors for the long-term mortality of patients with STEMI and a CTO.
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Oclusión Coronaria/fisiopatología , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST/terapia , Factores de Edad , Anciano , Enfermedad Crónica , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/mortalidad , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Insuficiencia Renal/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/mortalidad , Infarto del Miocardio con Elevación del ST/fisiopatología , Factores de Tiempo , Resultado del TratamientoRESUMEN
Sodium tanshinone IIA sulfonate (STS) has been reported to prevent Alzheimer's disease (AD). However, the mechanism is still unknown. In this study, two in vitro models, Aß-treated SH-SY5Y cells and SH-SY5Y human neuroblastoma cells transfected with APPsw (SH-SY5Y-APPsw cells), were employed to investigate the neuroprotective of STS. The results revealed that pretreatment with STS (1, 10 and 100 µmol/L) for 24 hours could protect against Aß (10 µmol/L)-induced cell toxicity in a dose-dependent manner in the SH-SY5Y cells. Sodium tanshinone IIA sulfonate decreased the concentrations of reactive oxygen species, malondialdehyde, NO and iNOS, while increased the activities of superoxide dismutase and glutathione peroxidase in the SH-SY5Y cells. Sodium tanshinone IIA sulfonate decreased the levels of inflammatory factors (IL-1ß, IL-6 and TNF-α) in the SH-SY5Y cells. In addition, Western blot results revealed that the expressions of neprilysin and insulin-degrading enzyme were up-regulated in the SH-SY5Y cells after STS treatment. Furthermore, ELISA and Western blot results showed that STS could decrease the levels of Aß. ELISA and qPCR results indicated that STS could increase α-secretase (ADAM10) activity and decrease ß-secretase (BACE1) activity. In conclusion, STS could protect against Aß-induced cell damage by modulating Aß degration and generation. Sodium tanshinone IIA sulfonate could be a promising candidate for AD treatment.
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Enfermedad de Alzheimer/prevención & control , Péptidos beta-Amiloides/metabolismo , Fármacos Neuroprotectores/farmacología , Fenantrenos/farmacología , Proteína ADAM10/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/análisis , Glutatión Peroxidasa/metabolismo , Humanos , Insulisina/metabolismo , Malondialdehído/metabolismo , Proteínas de la Membrana/metabolismo , Neprilisina/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
BACKGROUND: Although a variety of antidiabetic drugs have significant protective action on the cardiovascular system, it is still unclear which antidiabetic drugs can improve ventricular remodeling and fundamentally delay the process of heart failure. The purpose of this network meta-analysis is to compare the efficacy of sodium glucose cotransporter type 2 (SGLT-2) inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP-1) agonists, metformin (MET), sulfonylurea (SU) and thiazolidinediones (TZDs) in improving left ventricular (LV) remodeling in patients with type 2 diabetes (T2DM) and/or cardiovascular disease (CVD). METHODS: We searched articles published before October 18, 2019, regardless of language or data, in 4 electronic databases: PubMed, EMBASE, Cochrane Library and Web of Science. We included randomized controlled trials in this network meta-analysis, as well as a small number of cohort studies. The differences in the mean changes in left ventricular echocardiographic parameters between the treatment group and control group were evaluated. RESULTS: The difference in the mean change in LV ejection fraction (LVEF) between GLP-1 agonists and placebo in treatment effect was greater than zero (MD = 2.04% [0.64%, 3.43%]); similar results were observed for the difference in the mean change in LV end-diastolic diameter (LVEDD) between SGLT-2 inhibitors and placebo (MD = - 3.3 mm [5.31, - 5.29]), the difference in the mean change in LV end-systolic volume (LVESV) between GLP-1 agonists and placebo (MD = - 4.39 ml [- 8.09, - 0.7]); the difference in the mean change in E/e' between GLP-1 agonists and placebo (MD = - 1.05[- 1.78, - 0.32]); and the difference in the mean change in E/e' between SGLT-2 inhibitors and placebo (MD = - 1.91[- 3.39, - 0.43]). CONCLUSIONS: GLP-1 agonists are more significantly associated with improved LVEF, LVESV and E/e', SGLT-2 inhibitors are more significantly associated with improved LVEDD and E/e', and DPP-4 inhibitors are more strongly associated with a negative impact on LV end-diastolic volume (LVEDV) than are placebos. SGLT-2 inhibitors are superior to other drugs in pairwise comparisons.
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Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Incretinas/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Volumen Sistólico/efectos de los fármacos , Disfunción Ventricular Izquierda/tratamiento farmacológico , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , Adulto , Anciano , Biomarcadores/sangre , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Femenino , Humanos , Incretinas/efectos adversos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Disfunción Ventricular Izquierda/epidemiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
Signaling by the phytohormone abscisic acid (ABA) involves pre-mRNA splicing, a key process of post-transcriptional regulation of gene expression. However, the regulatory mechanism of alternative pre-mRNA splicing in ABA signaling remains largely unknown. We previously identified a pentatricopeptide repeat protein SOAR1 (suppressor of the ABAR-overexpressor 1) as a crucial player downstream of ABAR (putative ABA receptor) in ABA signaling. In this study, we identified a SOAR1 interaction partner USB1, which is an exoribonuclease catalyzing U6 production for spliceosome assembly. We reveal that together USB1 and SOAR1 negatively regulate ABA signaling in early seedling development. USB1 and SOAR1 are both required for the splicing of transcripts of numerous genes, including those involved in ABA signaling pathways, suggesting that USB1 and SOAR1 collaborate to regulate ABA signaling by affecting spliceosome assembly. These findings provide important new insights into the mechanistic control of alternative pre-mRNA splicing in the regulation of ABA-mediated plant responses to environmental cues.
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Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Exorribonucleasas/genética , Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las PlantasRESUMEN
The translation initiation factor eIF4E-binding protein-mediated regulation of protein translation by interfering with assembly of mRNA cap-binding complex eIF4F is well described in mammalian and yeast cells. However, it remains unknown whether a signaling regulator or pathway interacts directly with any translation initiation factor to modulate assembly of eIF4F in plant cells. Here, we report that the two isoforms of Arabidopsis eIF4G, eIFiso4G1 and eIFiso4G2, interact with a cytoplasmic-nuclear dual-localized pentatricopeptide repeat protein SOAR1 to regulate abscisic acid (ABA) signaling. SOAR1 inhibits interactions of eIFiso4E, eIF4Es, eIF4A1, eIF4B2 and poly(A)-binding protein PAB6 with eIFiso4G1 and eIFiso4G2, thereby inhibiting eIFiso4F/mixed eIF4F assembly and repressing translation initiation. SOAR1 binds mRNA of a key ABA-responsive gene ABI5 and cooperates with eIFiso4G1/2 to repress translation of ABI5. The binding of SOAR1 to ABI5 mRNA is likely to inhibit the interaction of SOAR1 with eIFiso4G1/2, suggesting a regulatory loop. Our findings identify a novel translation initiation repressor interfering with cap-binding complex assembly, and establish a link between cap-binding complex assembly and ABA signaling.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Factor 4G Eucariótico de Iniciación/metabolismo , Caperuzas de ARN/metabolismo , Transducción de Señal , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Germinación , Fenotipo , Polirribosomas/metabolismo , Unión Proteica , Subunidades de Proteína/metabolismo , ARN Mensajero/metabolismo , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Semillas/crecimiento & desarrolloRESUMEN
Natural daphnane diterpenoids, mainly distributed in plants of the Thymelaeaceae and Euphorbiaceae families, usually include a 5/7/6-tricyclic ring system with poly-hydroxyl groups located at C-3, C-4, C-5, C-9, C-13, C-14, or C-20, while some special types have a characteristic orthoester motif triaxially connectedat C-9, C-13, and C-14. The daphnane-type diterpenoids can be classified into five types: 6-epoxy daphnane diterpenoids, resiniferonoids, genkwanines, 1-alkyldaphnanes and rediocides, based on the oxygen-containing functions at rings B and C, as well as the substitution pattern of ring A. Up to now, nearly 200 daphnane-type diterpenoids have been isolated and elucidated from the Thymelaeaceae and Euphorbiaceae families. In-vitro and in-vivo experiments of these compounds have shown that they possess a wide range of biological activities, including anti-HIV, anti-cancer, anti-leukemic, neurotrophic, pesticidal and cytotoxic effects. A comprehensive account of the structural diversity is given in this review, along with the cytotoxic activities of daphnane-type diterpenoids, up to April 2019.
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Diterpenos/química , Euphorbiaceae/química , Thymelaeaceae/química , Animales , Fármacos Anti-VIH/química , Antineoplásicos/química , Humanos , Estructura MolecularRESUMEN
BACKGROUND Long noncoding RNAs (lncRNAs) recently have been implicated in the pathological processes of cardiovascular diseases. In this study, LncRNADisease database and PubMed database were used to screen myocardial infraction (MI)-related lncRNAs and to investigate the diagnostic role of lncRNAs in ST-segment elevation myocardial infraction (STEMI). MATERIAL AND METHODS Forty-six patients with STEMI and 40 healthy controls were included in the study. Venous blood samples acquired at different time points and the expression levels of lncRNAs in plasma were measured by qRT-PCR. In addition, other blood samples were collected before and after percutaneous coronary intervention (PCI). Correlation analysis and receiver operating characteristic (ROC) curve were used to assess the diagnosis value of the markers. All included patients were followed up for 12±1 months. RESULTS Nine MI-related lncRNAs were selected from the database. The qRT-PCR results showed that the expression of hypoxia inducible factor 1A antisense RNA 2 (aHIF), member 1 opposite strand/antisense transcript 1 (KCNQ1OT1), and mitochondrial long noncoding RNA uc022bqs.1 (LIPCAR) were significantly increased in patients with STEMI compared to the control patients. The ROC curve showed that LIPCAR (AUC=0.782, 95% CI: 0.707-0.0.894) had better diagnostic accuracy. Moreover, correlation analysis indicated that LIPCAR were positively correlated with myocardial enzymes and negatively correlated with left ventricular ejection fraction. The level of LIPCAR in STEMI patients after PCI was lower (P<0.05). Multivariate regression analysis indicated that higher levels of LIPCAR were independent predictors of major adverse cardiovascular events in patients with STEMI (HR=5.93; 95% CI, 1.46-9.77; P=0.001). CONCLUSIONS Highly expressed LIPCAR in plasma may serve as a warning sign for the diagnosis of STEMI.
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Infarto del Miocardio/genética , Intervención Coronaria Percutánea , ARN Largo no Codificante/sangre , Infarto del Miocardio con Elevación del ST/genética , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Casos y Controles , Ácidos Nucleicos Libres de Células/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Valor Predictivo de las Pruebas , Curva ROC , Infarto del Miocardio con Elevación del ST/sangre , Infarto del Miocardio con Elevación del ST/cirugíaRESUMEN
Nuclear factor Y (NF-Y) family proteins are involved in many developmental processes and responses to environmental cues in plants, but whether and how they regulate phytohormone abscisic acid (ABA) signaling need further studies. In the present study, we showed that over-expression of the NF-YC9 gene confers ABA hypersensitivity in both the early seedling growth and stomatal response, while down-regulation of NF-YC9 does not affect ABA response in these processes. We also showed that over-expression of the NF-YC9 gene confers salt and osmotic hypersensitivity in early seedling growth, which is likely to be directly associated with the ABA hypersensitivity. Further, we observed that NF-YC9 physically interacts with the ABA-responsive bZIP transcription factor ABA-INSENSITIVE5 (ABI5), and facilitates the function of ABI5 to bind and activate the promoter of a target gene EM6. Additionally, NF-YC9 up-regulates expression of the ABI5 gene in response to ABA. These findings show that NF-YC9 may be involved in ABA signaling as a positive regulator and likely functions redundantly together with other NF-YC members, and support the model that the NF-YC9 mediates ABA signaling via targeting to and aiding the ABA-responsive transcription factors such as ABI5.
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Ácido Abscísico/farmacología , Arabidopsis/genética , Factor de Unión a CCAAT/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Transducción de Señal , Arabidopsis/efectos de los fármacos , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factor de Unión a CCAAT/genética , Expresión Génica , Fenotipo , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/genética , Estomas de Plantas/fisiología , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Protoplastos , Plantones/efectos de los fármacos , Plantones/genética , Plantones/fisiología , Nicotiana/efectos de los fármacos , Nicotiana/genética , Nicotiana/fisiologíaRESUMEN
Although a lot of genes have been revealed to participate in abscisic acid (ABA) signaling, many of the additional components involved in ABA signaling remain to be discovered. Here we report that overexpression of MYB37, a R2R3 MYB subgroup 14 transcription factor in Arabidopsis thaliana, confers hypersensitive phenotypes to exogenous ABA in all the major ABA responses, including ABA-induced inhibition of seed germination, cotyledon greening and early seedling growth, and ABA-induced stomatal closure and inhibition of stomatal opening. Interestingly and importantly, MYB37-overexpression improves plant tolerance to drought, enhances growth of mature plants and seed productivity, thought it delays flowering, which suggests that this gene may be used for improving crop adaptability to drought environment and productivity. However, a myb37-1 knockout mutant displays wild-type ABA responses most likely due to a functional redundancy of the multiple MYB members. Real-time PCR analysis shows that upregulation of the MYB37 expression changes expression of a subset of ABA-responsive genes. Together, these findings suggest that the MYB37 transcription factor plays an important, positive role in plant response to ABA and drought stress, and meanwhile, it plays a positive role in the regulation of seed production.
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Ácido Abscísico/farmacología , Proteínas de Arabidopsis/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Sequías , Flores/efectos de los fármacos , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/genética , Germinación/efectos de los fármacos , Germinación/genética , Semillas/efectos de los fármacos , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Factores de Transcripción/genéticaRESUMEN
Receptor-like kinases (RLKs) have been reported to regulate many developmental and defense process, but only a few members have been functionally characterized. In the present study, our observations suggest that one of the RLKs, a membrane-localized cysteine-rich receptor-like protein kinase, CRK5, is involved in abscisic acid (ABA) signaling in Arabidopsis thaliana Overexpression of CRK5 increases ABA sensitivity in ABA-induced early seedling growth arrest and promotion of stomatal closure and inhibition of stomatal opening. Interestingly, and importantly, overexpression of CRK5 enhances plant drought tolerance without affecting plant growth at the mature stages and plant productivity. Transgenic lines overexpressing a mutated form of CRK5, CRK5 (K372E) with the change of the 372nd conserved amino acid residue from lysine to glutamic acid in its kinase domain, result in wild-type ABA and drought responses, supporting the role of CRK5 in ABA signaling. The loss-of-function mutation of the CRK5 gene does not affect the ABA response, while overexpression of two homologs of CRK5, CRK4 and CRK19, confers ABA responses, suggesting that these CRK members function redundantly. We further showed that WRKY18, WRKY40 and WRKY60 transcription factors repress the expression of CRK5, and that CRK5 likely functions upstream of ABI2 in ABA signaling. These findings help in understanding the complex ABA signaling network.
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Ácido Abscísico/fisiología , Proteínas de Arabidopsis/fisiología , Arabidopsis/metabolismo , Reguladores del Crecimiento de las Plantas/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Receptores de Superficie Celular/fisiología , Arabidopsis/fisiología , Deshidratación/metabolismo , Deshidratación/fisiopatología , Ensayo de Cambio de Movilidad Electroforética , Escherichia coli , Plantas Modificadas Genéticamente , Reacción en Cadena en Tiempo Real de la Polimerasa , Nicotiana , Técnicas del Sistema de Dos HíbridosRESUMEN
Whereas several mitochondrial/chloroplast pentatricopeptide repeat (PPR) proteins have been reported to regulate plant responses to abiotic stresses, no nucleus-localized PPR protein has been found to play role in these processes. In the present experiment, we provide evidence that a cytosol-nucleus dual-localized PPR protein SOAR1, functioning to negatively regulate abscisic acid (ABA) signaling in seed germination and postgermination growth, is a crucial, positive regulator of plant response to abiotic stresses. Downregulation of SOAR1 expression reduces, but upregulation of SOAR1 expression enhances, ABA sensitivity in ABA-induced promotion of stomatal closure and inhibition of stomatal opening, and plant tolerance to multiple, major abiotic stresses including drought, high salinity and low temperature. Interestingly and importantly, the SOAR1-overexpression lines display strong abilities to tolerate drought, salt and cold stresses, with surprisingly high resistance to salt stress in germination and postgermination growth of seeds that are able to potentially germinate in seawater, while no negative effect on plant growth and development was observed. So, the SOAR1 gene is likely useful for improvement of crops by transgenic manipulation to enhance crop productivity in stressful conditions. Further experimental data suggest that SOAR1 likely regulates plant stress responses at least partly by integrating ABA-dependent and independent signaling pathways, which is different from the ABI2/ABI1 type 2C protein phosphatase-mediated ABA signaling. These findings help to understand highly complicated stress and ABA signalling network.
Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiología , Arabidopsis/genética , Arabidopsis/fisiología , Ácido Abscísico/fisiología , Aclimatación/genética , Aclimatación/fisiología , Arabidopsis/crecimiento & desarrollo , Frío/efectos adversos , Sequías , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Germinación/genética , Germinación/fisiología , Presión Osmótica , Reguladores del Crecimiento de las Plantas/fisiología , Plantas Modificadas Genéticamente , Reacción en Cadena en Tiempo Real de la Polimerasa , Salinidad , Transducción de Señal , Estrés Fisiológico/genéticaRESUMEN
Magnesium-chelatase H subunit [CHLH/putative abscisic acid (ABA) receptor ABAR] positively regulates guard cell signalling in response to ABA, but the molecular mechanism remains largely unknown. A member of the sucrose nonfermenting 1 (SNF1)-related protein kinase 2 family, SnRK2.6/open stomata 1 (OST1)/SRK2E, which plays a critical role in ABA signalling in Arabidopsis guard cells, interacts with ABAR/CHLH. Neither mutation nor over-expression of the ABAR gene affects significantly ABA-insensitive phenotypes of stomatal movement in the OST1 knockout mutant allele srk2e. However, OST1 over-expression suppresses ABA-insensitive phenotypes of the ABAR mutant allele cch in stomatal movement. These genetic data support that OST1 functions downstream of ABAR in ABA signalling in guard cells. Consistent with this, ABAR protein is phosphorylated, but independently of the OST1 protein kinase. Two ABAR mutant alleles, cch and rtl1, show ABA insensitivity in ABA-induced reactive oxygen species and nitric oxide production, as well as in ABA-activated phosphorylation of a K(+) inward channel KAT1 in guard cells, which is consistent with that observed in the pyr1 pyl1 pyl2 pyl4 quadruple mutant of the well-characterized ABA receptor PYR/PYL/RCAR family acting upstream of OST1. These findings suggest that ABAR shares, at least in part, downstream signalling components with PYR/PYL/RCAR receptors for ABA in guard cells; though cch and rtl1 show strong ABA-insensitive phenotypes in both ABA-induced stomatal closure and inhibition of stomatal opening, while the pyr1 pyl1 pyl2 pyl4 quadruple mutant shows strong ABA insensitivity only in ABA-induced stomatal closure. These data establish a link between ABAR/CHLH and SnRK2.6/OST1 in guard cell signalling in response to ABA.
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Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , Liasas/genética , Estomas de Plantas/fisiología , Proteínas Quinasas/genética , Ácido Abscísico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Liasas/metabolismo , Mutación , Óxido Nítrico/metabolismo , Fosforilación , Estomas de Plantas/genética , Proteínas Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
A dominant suppressor of the ABAR overexpressor, soar1-1D, from CHLH/ABAR [coding for Mg-chelatase H subunit/putative abscisic acid (ABA) receptor (ABAR)] overexpression lines was screened to explore the mechanism of the ABAR-mediated ABA signalling. The SOAR1 gene encodes a pentatricopeptide repeat (PPR) protein which localizes to both the cytosol and nucleus. Down-regulation of SOAR1 strongly enhances, but up-regulation of SOAR1 almost completely impairs, ABA responses, revealing that SOAR1 is a critical, negative, regulator of ABA signalling. Further genetic evidence supports that SOAR1 functions downstream of ABAR and probably upstream of an ABA-responsive transcription factor ABI5. Changes in the SOAR1 expression alter expression of a subset of ABA-responsive genes including ABI5. These findings provide important information to elucidate further the functional mechanism of PPR proteins and the complicated ABA signalling network.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Germinación/fisiología , Regulación de la Expresión Génica de las Plantas/fisiologíaRESUMEN
Previous study showed that the magnesium-protoporphyrin IX chelatase H subunit (CHLH/ABAR) positively regulates abscisic acid (ABA) signaling. Here, we investigated the functions of a CHLH/ABAR interaction protein, the chloroplast co-chaperonin 20 (CPN20) in ABA signaling in Arabidopsis thaliana. We showed that down-expression of the CPN20 gene increases, but overexpression of the CPN20 gene reduces, ABA sensitivity in the major ABA responses including ABA-induced seed germination inhibition, postgermination growth arrest, promotion of stomatal closure and inhibition of stomatal opening. Genetic evidence supports that CPN20 functions downstream or at the same node of CHLH/ABAR, but upstream of the WRKY40 transcription factor. The other CPN20 interaction partners CPN10 and CPN60 are not involved in ABA signaling. Our findings show that CPN20 functions negatively in the ABAR-WRKY40 coupled ABA signaling independently of its co-chaperonin role, and provide a new insight into the role of co-chaperones in the regulation of plant responses to environmental cues.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/fisiología , Arabidopsis/metabolismo , Chaperoninas del Grupo I/fisiología , Transducción de Señal , Proteínas de Arabidopsis/genética , Regulación hacia Abajo , Chaperoninas del Grupo I/genética , Liasas/metabolismoRESUMEN
The light-harvesting chlorophyll a/b-binding (LHCB) proteins are the apoproteins of the light-harvesting complex of photosystem II. In the present study, we observed that downregulation of any of the six LHCB genes resulted in abscisic acid (ABA)-insensitive phenotypes in seed germination and post-germination growth, demonstrating that LHCB proteins are positively involved in these developmental processes in response to ABA. ABA was required for full expression of different LHCB members and physiologically high levels of ABA enhanced LHCB expression. The LHCB members were shown to be targets of an ABA-responsive WRKY-domain transcription factor, WRKY40, which represses LHCB expression to balance the positive function of the LHCBs in ABA signalling. These findings revealed that ABA is an inducer that fine-tunes LHCB expression at least partly through repressing the WRKY40 transcription repressor in stressful conditions in co-operation with light, which allows plants to adapt to environmental challenges.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Unión a Clorofila/metabolismo , Factores de Transcripción/metabolismo , Ácido Abscísico/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Unión a Clorofila/genética , Regulación de la Expresión Génica de las Plantas , Germinación , Complejos de Proteína Captadores de Luz/genética , Complejos de Proteína Captadores de Luz/metabolismo , Liasas/genética , Liasas/metabolismo , Mutación , Complejo de Proteína del Fotosistema II/genética , Complejo de Proteína del Fotosistema II/metabolismo , Regiones Promotoras Genéticas , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Transducción de Señal , Factores de Transcripción/genéticaRESUMEN
The phytohormone abscisic acid (ABA) plays a vital role in plant development and response to environmental challenges, but the complex networks of ABA signaling pathways are poorly understood. We previously reported that a chloroplast protein, the magnesium-protoporphyrin IX chelatase H subunit (CHLH/ABAR), functions as a receptor for ABA in Arabidopsis thaliana. Here, we report that ABAR spans the chloroplast envelope and that the cytosolic C terminus of ABAR interacts with a group of WRKY transcription factors (WRKY40, WRKY18, and WRKY60) that function as negative regulators of ABA signaling in seed germination and postgermination growth. WRKY40, a central negative regulator, inhibits expression of ABA-responsive genes, such as ABI5. In response to a high level of ABA signal that recruits WRKY40 from the nucleus to the cytosol and promotes ABAR-WRKY40 interaction, ABAR relieves the ABI5 gene of inhibition by repressing WRKY40 expression. These findings describe a unique ABA signaling pathway from the early signaling events to downstream gene expression.
Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Liasas/metabolismo , Proteínas de la Membrana/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Liasas/genética , Proteínas de la Membrana/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/genética , Regiones Promotoras Genéticas , ARN de Planta/genética , Transducción de Señal , Factores de Transcripción/genéticaRESUMEN
OBJECTIVE: To analyze the impact of efforts of community-based organizations (CBO) in HIV testing mobilization and case finding among men who have sex with men(MSM). METHODS: Results of HIV testing mobilization among MSM through CBOs in 15 program areas were collected and compared with corresponding HIV case reporting data to demonstrate the contribution of CBO-based HIV testing in HIV case finding among MSM from July 2008 to December 2011. Meanwhile,the proportion of screened HIV positives who received testing results notification,confirmatory test, following up and CD4 cell tests were analyzed and compared with those identified in medical institutions. RESULTS: A total of 196 075 HIV tests were performed for MSM, as a result of mobilization efforts of CBOs. Cumulatively 7704 new HIV cases were identified, accounting for 51.7% (7704/14 914) of all newly diagnosed HIV cases infected via homosexual sex in the program areas.Among the newly diagnosed MSM HIV infections in the program areas,the proportion of infections detected through the mobilization of CBOs increased from 35.4% (609/1722) in 2008 to 63.7% (2371/3722) in 2010, and 58.3% (3024/5189) in 2011. Compared with those identified through medical institutions, newly diagnosed MSM infections detected though CBOs testing mobilization have higher rates of receiving screening testing results notification (97.3% (4441/4563) vs 92.8% (13 140/14 153)) , (84.6% (2559/3024) vs 79.8% (5589/7002)) and CD4 cell tests (66.1% (1999/3024) vs 52.9% (3705/7002)), and a lower rate of receiving confirmatory test (78.6% (3588/4563) vs 85.6% (12 115/14 153)). CONCLUSION: CBOs can take their advantages in mobilizing MSM to receive HIV test, and MSM HIV cases detected through CBOs have become the main source of MSM HIV case finding in program areas.
Asunto(s)
Servicios de Salud Comunitaria , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Seropositividad para VIH , Promoción de la Salud , Humanos , Masculino , Tamizaje MasivoRESUMEN
[This retracts the article DOI: 10.3892/ol.2019.10040.].
RESUMEN
The grasshopper genus Mongolotettix Rehn, 1928 obtains 17 species distributed from the Far Eastern Asian countries, including China, Japan, Korea, Mongolia, and Russia [Bolvar, 1898; Uvarov, 1914; Caudell, 1921; Chogsomzhav, 1974; Li et Lian, 1994; Wan, Ren et Zhang, 1998; Xie et Li, 2000; Kim et Kim 2005; Shi et al, 2016; Shi et al, 2017; Yin et al, 2017; Zheng et al, 2017; Chen et al, 2018; Zhang et al, 2020; Cigliano et al, 2022, Shen et al, 2022]. In the present paper, we describe a new species of the genus from Jiangxi, China. Type specimens are deposited in the Shanghai Entomological Museum, Chinese Academy of Sciences, Shanghai, 200032, China.